In the Rule of Nines, what percentage does the anterior trunk represent?

In the Rule of Nines, what percentage does the anterior trunk represent?

• A. 18%
• B. 9%
• C. 1%
• D. 27%

Answer: (A)

In the Rule of Nines for adults, the front of the torso—the chest plus the abdomen—makes up 18% of the total body surface area. The trunk is divided into anterior and posterior halves, each contributing 18%, so the anterior trunk is 18%. That’s why the correct answer is 18%. The other values don’t correspond to a single major region in the Rule of Nines (for example, 9% is the head or a single arm, 1% isn’t used, and 27% isn’t a standard regional percentage). Remember, the whole trunk (front plus back) totals about 36%.

In the Rule of Nines for adults, the front of the torso—the chest plus the abdomen—makes up 18% of the total body surface area. The trunk is divided into anterior and posterior halves, each contributing 18%, so the anterior trunk is 18%. That’s why the correct answer is 18%. The other values don’t correspond to a single major region in the Rule of Nines (for example, 9% is the head or a single arm, 1% isn’t used, and 27% isn’t a standard regional percentage). Remember, the whole trunk (front plus back) totals about 36%.